United Rentals
Autonomous Compact Track Loader

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We designed an automated solar panel installation workflow for safe, efficient human-machine collaboration

The Challenge

Our client approached us to expand on a previous engagement: autonomous forklift technology. Our task was to take the same technology and apply it to a Compact Track Loader vehicle. Their goal was to improve process efficiency on construction sites and improve the overall safety of each crew-member in the field. The challenge involved safely operating a 6-ton vehicle while driving down narrow alleys between expensive solar panels and field crew workers, which required a much more complex strategy than a simple retrofit.

Our Solution

Fresh was the full-service engineering and integration partner. Our teams were responsible for the requirements development, safety analysis, design of the autonomous hardware, firmware, and control software, and developing the fleet management and orchestration software. We also designed the field network for robot connectivity and the telemetry system for vehicle monitoring and conducted end-to-end testing and service across multiple sites.

The partnership grew into a multi-year engagement to create an optimized program for delivering heavy parts and material with pinpoint accuracy to create seamless construction site operations.

Key Contributors

Gene Hancock
Gene Hancock
Tyler Bowen
Tyler Bowen
Greg Starr
Greg Starr
Likhi Ondov
Likhi Ondov
Mariana Araújo
Mariana Araújo
Jonathan Shimoda
Jonathan Shimoda
Ian McDermott
Ian McDermott
Tiffany Peil
Tiffany Peil
Karin Draughn
Karin Draughn
Richard Johnson
Richard Johnson
Jeff Alexander
Jeff Alexander
Laird Free
Laird Free
Hunter Fite
Hunter Fite
Aravind Ravi
Aravind Ravi
Jeff Dalton
Jeff Dalton
Michelle Tolfa
Michelle Tolfa
BradJacula
BradJacula
Taylor Kendall
Taylor Kendall
Mitch Tolson
Mitch Tolson
Fraser Midstokke
Fraser Midstokke
Yanick Duchesne
Yanick Duchesne
Cole Wilhelm
Cole Wilhelm
Tylor Echols
Tylor Echols
Darshit Dalal
Darshit Dalal
GM Ogle
GM Ogle
Maximillian West
Maximillian West
Stefan Petkov
Stefan Petkov
Nathan Turin-Mead
Nathan Turin-Mead
Matt Druyos
Matt Druyos
Joshua Hockett
Joshua Hockett
John Houston
John Houston
Nissa Van Meter
Nissa Van Meter
Grant Ritter
Grant Ritter
Vishal Prabhu
Vishal Prabhu
Steve Hulet
Steve Hulet
Aaron Edgington
Aaron Edgington
Jamie Garza
Jamie Garza
Kurt Daniels
Kurt Daniels
Sonika Latkar
Sonika Latkar
Logan Bean
Logan Bean
Griffin Dziok
Griffin Dziok
Mark Nader
Mark Nader
Jeff Bick
Jeff Bick
Jeff Dance
Jeff Dance
Terence Tam
Terence Tam
Dean Fortier
Dean Fortier
David Lopez
David Lopez
Conor Wolfin
Conor Wolfin

An optimized industrial automation platform

The team built a flexible software platform and control system that can be customized to integrate with different types, makes, and models of construction equipment. The solutions can effectively transform most off-the-shelf construction equipment into intelligent, self-driving vehicles.

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10+ sensor technologies

Rear GPS Antenna: Accurate global positioning of the vehicle for autonomous navigation

900Mhz Antenna: Remote communication with the local server

Rear LiDAR: Object detection around the vehicle for navigation purposes

Boom Encoder: Accurate position detection of the lift arm

Rear Scanner: Obstacle detection intended for safety in and around the vehicle

Track Encoder: Track detection for accurate navigation

Electronics Enclosure: Command and control components for various sensors

Front GPS Antenna: Accurate global positioning of the vehicle for autonomous navigation

Front LiDAR: Object detection around the vehicle for navigation purposes

Security Camera & Intention Lamp: Security camera to capture and monitor remote events; intention lamp used to indicate vehicle status

Front Scanner: Obstacle detection intended for safety in and around the vehicle

National Instruments integration

Compact track loaders were retrofitted with a sensor package to detect obstacles. The vehicles were integrated with National Instruments equipment and software using control logic, allowing the vehicles to drive autonomously. The vehicles were designed to follow a route plotted by a Fresh-developed tablet-based path-planning application to deliver parts and equipment from a staging area to installation crews throughout a solar site.

This automation and precision resulted in immediate productivity gains in installation time, allowed for less wear and tear on the installer, prevented equipment damage during the vehicle’s operation, and freed up the operator for other tasks because one less worker was needed to drive the vehicle.

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Delivering solutions with velocity

From idea to implementation, the autonomous vehicle for moving solar panels was delivered in less than six months. Once the prototype was proven to work, the team continued refining and iterating the system and now have dozens of autonomous vehicles doing work on solar farms.


Key Results

78

Fully autonomous CTLs manufactured, supporting scale and demand.

2870

Solar panels installed in seven days.

2.5cm

Met safety target of 2.5 cm of accuracy for safe collaboration.

20

CTLs deployed to 500-acre sites.